- YY syndrome.

YY syndrome

*Def :- A genetic condition where males have an extra Y chromosome (i.e XYY) in each of their cells .

* This is not usually an inherited condition but a defect that occurs during cell division.

* Often the condition is asymptomatic.

* Incidence :- rare disease.

*Synonyms:-

• Diplo-Y Syndrome.
• Polysomy Y.
• XYY Chromosome Pattern.

*Pathophysiology:-
Due to non-disjunction of chromosome Y during 2nd meiotic division so YY sperm when fertilizes an ovum carrying X chromosome give baby with XYY.

*Karyotype :-
47,XYY

* Clinical picture:-

• Tall stature
• Subnormal intelligence.
• Developmental delays.
• May show aggressive tendency or antisocial behavior.

Return to list of medical syndromes here

*References:-
- Principles of histology vol1,staff members ,faculty of medicine,mansoura university,ch3,p.g75,76.